Many aqueous systems utilize thickeners to provide a particular formulation with a desired viscosity. For example, certain aqueous thickeners are utilized in the formulation of a number of drilling muds. Other aqueous thickeners are utilized in the formulation of a number of polishing and cleaning compositions. Still other aqueous thickeners are utilized in the manufacture and/or preparation of a number of personal-care and food-product formulations as well as certain pharmaceuticals. While other aqueous thickeners are utilized in the formulation of a number of coating compositions such as latex paints.
In recent years, latex paints, i.e. paints based on aqueous emulsions or so-called "dispersions" of synthetic organic polymers, have come into widespread use because they can easily be applied to a substrate, because they are easily cleaned from brushes and rollers, and because they are generally free of objectionable odor.
Thickeners are commonly used in latex paint formulations, as well as in a variety of other coating compositions, to provide desired thickening properties. There are many types of thickeners now used in paints and other coating compositions.
Water-soluble materials employed as thickeners include natural gums and resins, such as starch, gum arabic, certain modified-starch products, dextrins, sodium alginates, gums (such as tragacanths) and other such compounds. Synthetic materials employed as thickeners include polyvinyl alcohol, polyacrylamide, polyacrylic acid and certain salts thereof, methyl cellulose and other cellulose derivatives such as carboxymethyl cellulose and hydroxyethyl cellulose, polyvinyl pyrrolidone, polyvinyl methylether, polyethylene oxides and copolymers of polyvinyl methylether and maleic anhydride.
However, water-soluble polymers derived from cellulose and other natural products are becoming increasingly expensive to produce because of high capital, energy, and waste-disposal costs.
The current trend, therefore, is to utilize specially-prepared polymeric thickeners in the manufacture of a number of formulations so as to provide such formulations with certain desired viscosity properties at relatively low cost.
An effective thickener should be used in minimum amount, however, and should not affect the basic properties of the aqueous system in which it is used.
Accordingly, disclosed herein is a novel polymeric thickener as well as a novel method for its manufacture.